No. One end is the lightning connector which will plug into your iPad Mini, the other end is a 30 pin SOCKET (not a plug).
It can only be used to connect a device or cable with a 30pin plug to the new iphone5 or ipad mini etc..
So you could use it to connect a speaker dock with the old connector to the new devices with a lightning socket, or if your car has an ipod interface with the old 30 pin plug or to use with an old usb to 30 pin dock cable.

Also note the size...20cm's long. The picture is accurate if you imagine the bit of cable you can't see is literally looped just out of shot!

To connect your ipad Mini to an iPhone, you could tether it with WiFi. Turn on 'Personal Hotspot' and then connect your iPad to the new wifi you just created.

No, it doesn't support that. That function was never supported on any model of iPad or iPhone.
You can tether using Wi-Fi or Bluetooth between an iPhone or iPad. Tethering an iPhone via a Dock Connector is only for PC or Mac.